Molded resin product and process for surface treatment thereof

ABSTRACT

A molded resin product includes a substrate made of a transparent resin, opaque coating film disposed on rear surface of the substrate except for an area set aside for a patterned portion, a transparent resin material disposed in the area set aside for the patterned portion on the rear surface of the substrate, and an opaque reflection coating or a half-reflective coating laminated to the transparent resin material. Under this configuration, the patterned portion looks as if it pops up from the rear surface of the substrate. If a half-reflective coating is used, the pattern is visible through the half-reflective coating when the pattern is viewed from the rear surface of the lid of a molded resin product.

This is a Divisional of application Ser. No. 12/224,315 filed Aug. 22,2008, which in turn is a National Phase of PCT/JP2007/057272 filed Mar.30, 2007, which claims the benefit of Japanese Patent Application Nos.2006-099176 filed Mar. 31, 2006; 2006-125619 filed Apr. 28, 2006; and2006-179454 filed Jun. 29, 2006. The disclosures of the priorapplications are hereby incorporated by reference herein in theirentirety.

TECHNICAL FIELD

This invention relates to a molded resin product having a pattern formedon the surface in such a way that the pattern looks as if it pops upfrom the background, and to a process for surface treatment of themolded resin product having a stereoscopic pattern formed on the resinsurface.

BACKGROUND ART

In the field of cosmetic containers, metallic decorations have been inuse for improved appearance. The containers are treated by a hotstamping method to apply metallic decorations stereoscopically to thecontainers.

Printing has also been utilized to allow a letter/letters or apattern/patterns to pop up on the surface and thus to give atmosphere ofquality products to the containers.

-   [Patent document 1] Published patent application JP1994-286397A

DISCLOSURE OF THE INVENTION Problems To Be Solved By the Invention

However, if asperity was given to the surfaces of the container, aproblem of higher cost arose because the mold required additionalworking. In addition, hot stamping was time-consuming.

On the other hand, those containers having been given athree-dimensional appearance by means of printing can be manufactured ata low cost because asperity need not be formed on the surfaces, but thesurfaces are apt to give a flat impression. It was very difficult togive the container a three-dimensional appearance through the printingmeans without forming asperity on the surfaces and to obtain aresin-made container having atmosphere of a quality product.

An object of this invention is to provide a molded resin product havingatmosphere of a quality product as a result of a stereoscopic patternthat is formed on the container surfaces by a simple method such ascoating or vapor deposition. Another object of this invention is toprovide a surface treatment process for laying a stereoscopic pattern ofhigh quality on the resin surfaces.

Means Of Solving the Problems

Intended to give solutions to the above problems, this inventioncomprises a molded resin product and a process for surface treatmentthereof, as will be described below.

The molded resin product of this invention comprises a substrate made ofa transparent resin, opaque coating film disposed on the rear surface ofthe substrate except for an area set aside for the patterned portion, atransparent resin material disposed on the rear surface of the substratein the area set aside for the patterned portion, and an opaquereflection coating or a half-reflective coating disposed on the rearsurface of the transparent resin material.

The substrate is a molded product made of a transparent resin used tomold resin product components, such as the container body and the lid.The substrate would be suitable as long as it transmits light, and maybe colored. Thickness of the substrate is not specifically limiting. Thethickness may not be uniform but can be varied. In addition, thesubstrate may not be flat but can be curved in a given shape, or may bemolded into a desired shape.

Opaque coating film is formed by applying a colored coating material onthe rear surface of the substrate. The color of the coating material isnot limited, but preferably the coating material has a dark color suchas black. A patterned portion is formed by not allowing the coating filmto be left on the substrate. For example, the coating material isapplied to the entire rear surface of the substrate, and then laser beamis irradiated to the patterned portion to remove the coating filmtherefrom. Or printing may be used to apply the coating film to theareas other than the patterned portion, and the patterned portion isformed by the remaining areas where no coating film has been printed. Ifa patterned area is formed by printing, use is made of serigraph. Thepatterned portion thus formed remains as transparent as the substrate.The substrate corresponding to the patterned portion has a smoothsurface.

The patterned portion may also be formed by applying a thin film ontothe rear surface of the substrate wherein the thin film have acutting-out portion of the shape of the pattern.

The transparent resin material made of a transparent ink or resin isdisposed so as to embed the pattern in the area where there is nocoating film. The layer of this material on the rear surface of thesubstrate is formed to have the same thickness as the coating film andto have a flat surface. However, this thickness of the transparent resinmaterial may be reduced to a level thinner than the thickness of thecoating film, or may be increased and disposed so as to embed thecoating film. Alternatively, the layer of the transparent resin materialmay be formed by serigraph so as to have a roughly uniform thickness andto cover the respective surfaces of both the coating film and thesubstrate in a continuous manner over a wide area including thepatterned portion.

Like the substrate, the transparent resin material, too, may be coloredas long as it is transparent. An additive or additives may beincorporated into the inside of the transparent resin material. As theadditives, there may be mentioned a lame material having high lightreflectivity or a particulate member of a certain color. The particulatematerials are not limited to spherical fine particles but may havecertain shapes such as needles, flakes, or stars. The additive may beuniformly incorporated inside the transparent resin material, or may beconcentrated in the upper portion or precipitated in the lower portionby changing its specific gravity. The additive may not belight-reflective or may have a certain color or colors.

It is preferred that, regarding material quality, the transparent resinmaterial has a refractive index different from that of the substrate.Different refractive indexes cause a part of light to reflect on theboundary surface between the transparent resin material and thesubstrate. Thus, incident light (including reflected light) is refractedwhen the light passes through this boundary surface.

Opaque reflection coating is preferably in the form of a reflectivesurface or a mirror surface. This coating may also be made of highlyreflective, bright colored film. The reflective or mirror surface isformed by, for example, vapor deposition of a metal. The opaquereflection coating is formed in the area corresponding to at least apatterned portion on the rear surface of the substrate, but may also beformed directly on the rear surface of the substrate under the conditionthat there is no layer of the transparent resin material in thepatterned portion.

The opaque reflection coating may be formed by coating the patternedportion with paint or by applying opaque sheet-like film having areflective surface to the patterned portion. Hot stamping, for example,is used to apply the film to the patterned portion. The opaquereflection coating is transferred from transfer foil to the substrateover a wide area including the patterned portion.

In addition, opaque reflection coating may be formed on the rear surfaceof the substrate by pasting a resin member having a reflective surfaceto that rear surface or by combining such a member with another coating.In all these cases, the opaque reflection coating may also be colored onthe surface.

A half-reflective coating is a film provided with a half-reflectivesurface on the transparent resin material side. The half-reflectivecoating is a member also referred to as a half mirror. It has a propertyof reflecting a part of the light incoming from the reflective surfaceand partly transmitting the rest of the light to the rear side. Thehalf-reflective coating is formed by depositing a metal composition ontothe surface of, for example, a resin film. In that case, the metal isnot deposited completely until a perfect reflective surface is formed onthe resin film, but the deposition is stopped halfway to form ahalf-reflective coating on the resin surface. Reflectance ortransmittance of the half-reflective coating is arbitrarily determined.For example, reflectance is set by using the color or brightness of thesubstrate or the opaque reflection coating as the standard. Thereflectance of a half-reflective coating is set so that there isreflection of a part of light on the reflective side of thehalf-reflective coating and that a part of light is transmitted throughthe half-reflective coating to the rear side. The rear surface of thehalf-reflective coating or the rear side of the molded resin product maybe tinged with a certain color as long as the coating islight-transmitting.

The half-reflective coating is formed at least in the patterned area onthe rear surface of the substrate. This coating may be directly formedon the rear surface of the substrate under the condition that there isno transparent resin material in the patterned portion. Thehalf-reflective coating may also be formed over the entire rear surfaceof the substrate, or may be formed in a predetermined shape after thepatterned portion has been covered with a transparent resin material. Inaddition, the half-reflective coating may be combined with a totalreflection coating. In that case, a half-reflective coating and a totalreflection coating are newly formed.

The half-reflective coating may be formed by coating the patternedportion with paint or by applying a sheet-like film having ahalf-reflective surface to the patterned portion. Hot stamping, forexample, is used to apply the film to the patterned portion. Thehalf-reflective coating is transferred from transfer foil to thesubstrate over a wide area including the patterned portion.

In addition, the half-reflective coating may be formed on the rearsurface of the substrate by pasting a resin member having ahalf-reflective surface to that rear surface or by combining such amember with another coating.

The half-reflective coating may have a colored reflective surface. Thecoating film having a reflective surface or the resin member (asubstrate for the half-reflective coating) may also be colored. Ineither way, the patterned portion having a predetermined color is formedon the rear side of the molded resin product.

The resin product of this invention is applicable not only to containersbut also to other resin products such as carved ornament, or to productparts, such as dial plates, switches, or knobs.

The molded resin product formed by the above process may be utilized bypasting it to the surface of a product or by embedding it in the surfaceof a product. An additive having light reflectivity may be incorporatedinto the substrate and the coating film, as incorporated to thetransparent resin material.

Effects of the Invention

In the case of the molded resin product of this invention, the patternedportion, i.e., the area filled with the transparent resin material,looks as if the pattern pops up from the rear surface of the substrate.The pattern is highly visible as it is reflected against thedark-colored background of the coating film. Furthermore, an illusion iscreated and given to human eyes because of a difference in refractiveindex between the substrate and the transparent resin material. Theopaque reflection coating or the half-reflective coating laid betweenthe substrate and the layer of the transparent resin material looks asif it is not on the rear side of the substrate but is above the rearsurface of the substrate.

If the opaque reflection coating or the half-reflective coating isformed in mirror finish, the pattern has glaze and looks as if it popsup from the coating film, especially when the coating film is black- ordark-colored. In addition, there are cases where the transparent resinmaterial looks as if it has the color of the opaque reflection coatingor the half-reflective coating, thus giving atmosphere of high qualityto the container.

The molded resin product may happen to be, for example, the lid of acontainer or a part of an article wherein the rear surface is alsovisible when the product is opened. In such a case, a half-reflectivecoating is utilized to form a stereoscopic pattern on the lid surface.And when the lid is opened, the same pattern is also visible on the rearsurface of the lid due to the light that has transmitted through thehalf-reflective coating. Therefore, from the outer surface of the moldedresin product, it is impossible to look inside through the patternedportion because of the half-reflective coating that reflects a part oflight, and a stereoscopic pattern pops up on the surface. And from therear surface of the molded resin product, there appears the pale or darksee-through pattern on the rear surface of the molded resin product.

The reflective surface of the half-reflective coating may be formed in areverse manner so that the upper surface of the molded resin productbecomes the rear surface, and vice versa.

The molded resin product of this invention having a stereoscopic patterncan be manufactured at a low cost because the substrate is molded from atransparent resin, followed by mere surface treatment on the rearsurface. Any desired appearance can be obtained by picking out a resinof any appropriate color for the substrate, the coating film, thetransparent resin material, the opaque refraction coating, and/or thehalf-reflective coating.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view of the molded resin product in one embodimentof this invention.

FIGS. 2( a)-(e) are explanatory diagrams showing the surface treatmentprocess of this invention.

FIG. 3 is a sectional view of the molded resin product in anotherembodiment of this invention.

FIG. 4 is an explanatory diagram showing another embodiment of thesurface treatment process.

FIG. 5 is an explanatory diagram showing another embodiment of thesurface treatment process.

FIG. 6 is an explanatory diagram showing another embodiment of themolded resin product.

FIG. 7 is an exploded view showing another embodiment of the surfacetreatment process.

FIG. 8 is a full perspective view of the molded resin product in anotherembodiment of this invention.

FIG. 9 is an explanatory diagram showing another embodiment of thesurface treatment process.

FIG. 10 is an explanatory diagram showing another embodiment of thesurface treatment process.

FIG. 11 is a sectional view of the molded resin product in anotherembodiment of this invention.

FIG. 12 is a perspective view showing the entire cosmetic container.

FIG. 13 is a perspective view of the cosmetic container of FIG. 12 in astate where the lid is opened.

EXPLANATION OF CODES

-   -   1. Cosmetic container    -   3. Patterned portion    -   4. Lid    -   6. Container body    -   8. Substrate    -   10. Coating film    -   12. Transparent resin material    -   14 a. Reflection coating    -   14 b. Half-reflective coating    -   15 a. Reflecting member    -   15 b. Half-reflecting member    -   16. Resin member    -   17 a. Reflecting member    -   17 b. Half-reflecting member    -   18. Flake

PREFERRED EMBODIMENTS OF THE INVENTION

This invention is further described with respect to preferredembodiments of this invention, now referring to the drawings (FIGS.1-13). FIGS. 1-11 show some members coded with 14 a (14 b), 15 a (15 b),17 a (17 b), etc. These codes accompanied by the codes in parenthesesindicate that the member is a reflection coating 14 a or ahalf-reflective coating 14 b; a reflecting member 15 a or ahalf-reflecting member 15 b; or a reflecting member 17 a or ahalf-reflecting member 17 b.

FIG. 12 shows a cosmetic container 2 for which the surface treatmentprocess of this invention has been used. The cosmetic container 2 is amolded resin product and comprises a lid 4 and a main body 6 to whichthe lid 4 is fitted in a manner that the lid 4 can be opened or closed.The lid 4 has a pattern of A that has been formed by the surfacetreatment.

FIG. 1 shows a vertical section of a lid 4, which comprises a substrate8, i.e., the portion determining the basic shape of the lid 4, a coatingfilm 10 applied to the rear surface of the substrate 8, a transparentresin material 12 filled between two adjacent areas of the coating film,and a reflection coating 14 a or a half-reflective coating 14 b.

The substrate 8 is made of a transparent synthetic resin and is moldedby, for example, injection molding. The coating film 10 is opaque andblack in color. It is disposed in the area other than the patternedportion 3. In other words, the patterned portion 3 is formed by notlaying the coating film 10 thereon.

The transparent resin material 12 is disposed in the patterned portion 3where there is no coating film 10. The reflection coating 14 a or thehalf-reflective coating 14 b is formed uniformly on the surfaces of boththe coating film 10 and the transparent resin material 12, with at leastthe surface of the lid 4 being used as the reflective or half-reflectivesurface.

If a half-reflecting coating 14 b is used, the reflectance ortransmittance is set at a value in such a range that the half-reflectivecoating 14 b serves as the reflective surface to reflect light when thelid 4 is viewed from the upper surface, but that the patterned portion 3is visible through the half-reflective coating 14 b when the lid 4 isviewed from the rear surface.

The surface treatment process used for the lid 4 is described below.

A coating material is applied to the entire rear surface of thesubstrate 8 shown in FIG. 2( a). Thus, the coating film 10 is disposedover the entire rear surface of the substrate 8, as shown in FIG. 2( b).Then, the patterned portion 3, i.e., a letter A in FIG. 12, isirradiated with laser beam to remove the coating film 10 from thisportion. The coating film 10 is left to stay in the area other than thepatterned portion 3, where there has been no laser beam irradiation(FIG. 2( c)). The edges of the patterned portion 3 are smooth andvertical to the substrate 8, as shown in FIG. 2( c).

Then, the patterned portion 3 having no coating film 10 is filled withthe transparent resin material 12, which is laid in the liquid state andis left to solidify in the patterned portion 3. The surface of the layerof the transparent resin material 12 is formed flatly at the same heightas the coating film 10, as shown in FIG. 2( d).

The reflection coating 14 a or the half-reflective coating 14 b isuniformly formed on the surfaces of the coating film 10 and thetransparent resin material 12, as shown in FIG. 2( e). The vapordeposition of a metal is used so that the reflection coating 14 a or thehalf-reflective coating 14 b has a reflective surface on the upper sideof the lid 4.

Since the lid 4 receives the above-described surface treatment, thereflection coating 14 a or the half-reflecting coating 14 b is formed inthe shape of the patterned portion 3. If one looks down at the cosmeticcontainer 2, the glossy pattern A is visible against the background ofthe coating film 10. The pattern of A looks as if it pops up from thesurface of the coating film 10.

Since the reflection coating 14 a or the half-reflective coating 14 b isformed on the rear surface of the transparent resin material 12, it isactually disposed under the coating film 10. But this reflection coating14 a or half-reflective coating 14 b is appealing because it reflectslight and happens to create an illusion to human eyes, as derived from adifference in refractive index between the substrate 8 and thetransparent resin material 12. Thus, the pattern A looks as if it isdisposed above the coating film 10.

Therefore, the cosmetic container 2 looks beautiful as the patternedportion 3 pops up on the surface of the black lid 4. In some cases, thetransparent resin material 12 looks as if it is colored with a tinge ofthe coating film 10 under the effects of reflection or transmission.Thus, the surface treatment of this invention can create the atmosphereof a quality product.

If the halve-reflective coating 14 b is used, light passes through thecoating 14 b because it has light transmittance. When the lid 4 isopened, the pattern A is visible half-transparently from the rearsurface, as shown in FIG. 13. Since the pattern A is visible from therear surface due to a part of light that has passed through thehalf-reflective coating 14 b, the look of the pattern A from the rearsurface gives different atmosphere. How the half-reflective coating 14 breflects light changes with the angle of the lid 4 that is opened orclosed relative to the container body. As a result, image of the patternA varies delicately as observed from the rear surface.

Although the coating film 10 was removed from the patterned portion 3 inthe above embodiment, this invention is not limited to the embodimentdescribed above. The patterned portion 3 may also be formed by printingthe substrate 8 directly, e.g., by serigraph, while leaving apredetermined pattern to be outlined on the printed background.

FIG. 3 shows another embodiment of the lid 4.

In this embodiment, the process of surface treatment goes on similarlyup to the step of FIG. 2( c) in the first embodiment. Then, thetransparent resin material 12 is formed at roughly uniform thickness onthe surfaces of the coating film 10 and the substrate 8. The reflectioncoating 14 a or the half-reflective coating 14 b is also formed over theentire surface of the transparent resin material 12 in the same way asin the first embodiment. In this embodiment, the patterned portion 3pops up just as it does in the first embodiment.

FIGS. 4 and 5 show other embodiments of the surface treatment processapplied to the lid 4.

In the embodiment shown in FIG. 4, a sheet-like reflecting member 15 aor half-reflecting member 15 b is used to form an opaque reflectioncoating or a half-reflective coating on the rear surface of thesubstrate 8. The steps have gone similarly up to FIG. 2( d) as in thefirst embodiment, and in the next step, the reflecting member 15 a orthe half-reflecting member 15 b is laid over both surfaces of thecoating film 10 and the transparent resin material 12.

The reflecting member 15 a or the half-reflecting member 15 b is a thinfilm member, and the reflective or half-reflective surface has beenformed on the side facing the substrate 8. The reflecting member 15 a orthe half-reflecting member 15 b is adhered to the surfaces of thecoating film 10 and the transparent resin material 12 by using anadhesive agent.

Thus, the opaque reflection coating or the half-reflective coating ofthese embodiments is formed in the patterned portion 3 of the lid 4,giving the same effect as in the first embodiment.

In the embodiment shown in FIG. 5, the process of surface treatment goeson similarly up to the step of FIG. 2( c) as in the first embodiment.Then, the transparent resin material 12 is formed at roughly uniformthickness on the surfaces of the coating film 10 and the substrate 8. Areflecting member 15 a or a half-reflecting member 15 b is laid over thesurface of the transparent resin material 12. The reflecting member 15 aor the half-reflecting member 15 b is a thin film member, and thereflective or half-reflective surface is formed on the side facing thesubstrate 8. The reflecting member 15 a or the half-reflecting member 15b is adhered to the surface of the transparent resin material 12 byusing an adhesive agent.

FIG. 6 shows an embodiment in which a reflecting member 17 a or ahalf-reflecting member 17 b is disposed on the surface of thetransparent resin material 12 by using the hot stamping method. In thisembodiment, the coating film 10 is disposed on the substrate 8 except inthe patterned portion 3, and the transparent resin material 12 isapplied to roughly entire surface of the substrate 8. Thereafter, asshown in FIG. 7, the reflecting member 17 a or the half-reflectingmember 17 b is transferred from transfer foil 20 and is applied to thepatterned portion 3 by using hot stamping. The transfer foil 20comprises a thin film material 24 laminated on a sheet-like substrate22. When a heated die (not shown) is pressed onto the transfer foil 20,the thin film material 24 is broken away from the substrate 22 in theshape of the die, and is attached to a target layer, such as thesubstrate 8. The reflecting member 17 a or the half-reflecting member 17b is provided with a reflective surface or a half-reflective surface onthe side facing the substrate 8 in the same way as described above, andis attached to the rear surface of the substrate 8 over a wide areaincluding the patterned area 3, as shown in FIG. 8.

This embodiment, too, gives the same effect as observed in the firstembodiment described above because the opaque reflection coating or thehalf-reflective coating is formed similarly in the patterned portion 3of the lid 4.

In addition, the reflecting member 15 a, 17 a or the half-reflectivemember 15 b, 17 b may be laid over the surface of the transparent resinmaterial 12 by using hot stamping or other printing methods. Thereflecting member 15 a, 17 a or the half-reflective member 15 b, 17 bneed not be in close contact with the surface of the transparent resinmaterial 12, but may have void in corners. Furthermore, there may be airspaces between the transparent resin material 12 and the reflectingmember 15 a, 17 a or the half-reflective member 15 b, 17 b. Although thereflecting member 15 a, 17 a or the half-reflective member 15 b, 17 bmay be laid over the surface of the transparent resin material 12 byusing hot stamping, laying of such a member is not limited to theembodiment shown in FIG. 6. The hot stamping method may be utilized in acase where the transparent resin material 12 is made of an ink and isformed at the same height as the coating film 10.

FIGS. 9 and 10 show still other embodiments, in which the reflectioncoating 14 a or the half-reflective coating 14 b is formed on onesurface of a resin member 16 and is attached to the rear surface of thesubstrate 8 to form the opaque reflection coating or the half-reflectivecoating. The resin member 16 can be formed in advance so as to beadapted to the shape of rear surface of the substrate 8 or can beflexible so as to deform appropriately according to the shape of therear surface of the substrate 8.

In FIGS. 9 and 10, the configurations of the coating film 10 and thetransparent resin material 12 attached to the substrate 8 are similar tothose described for FIGS. 4 and 5. The resin member 16 is fitted to thesubstrate 8 by adhesion or assembly. The fitting method is notrestricted specifically.

The same effect as described above can be achieved by forming therefection coating or the half-reflective coating on the resin member 16and fitting the member 16 to the substrate 8 to form an opaquereflection coating or a half-reflecting coating over the patternedportion 3. Furthermore, a stereoscopic pattern may be formed by allowingthe resin member 16 to configure the basic shape of a molded resinproduct according to this invention and by fitting the resin member 16to the substrate 8.

FIG. 11 shows still another embodiment. In this embodiment, small flakes18 having light reflectivity are incorporated into the transparent resinmaterial 12. The flakes 18 may be mixed in advance with the transparentresin material 12; or mixed with the transparent resin material 12 afterit has been applied to the substrate 8. This enables light to bereflected inside the transparent resin material 12 with which thepatterned portion 3 is filled up. Therefore, the patterned portion 3 canhave new atmosphere that is different from the patterned portion 3described above.

If a half-reflective coating 14 b is utilized, the patterned portion 3having flakes 18 incorporated therein can be seen through thehalf-reflective coating 14 b when the lid 4 is viewed from the rearsurface.

The incorporation of such light-reflective flakes 18 may be used for thelid 4 that is formed by either method shown in FIG. 9 or 10. Flakes areflat, thin pieces, but they may also have such shapes as particles,needles, or stars, as determined previously. The flakes may not bereflective to light, but have a certain color or colors.

In addition, light-reflective flakes may be incorporated into thesubstrate 8 or the coating film 10 in the same manner as with thetransparent resin material 12.

In the case of FIG. 10, the reflection coating 14 a or thehalf-reflective coating 14 b is preferably attached closely to thesurface of the transparent resin material 12, but the close contact isnot always necessary, and some gap or air space may exist between thetransparent resin material 12 and the reflection coating 14 a or thehalf-reflective coating 14 b.

The patterned portion 3 is not limited to the letter A. Moreover,letters or patterns may have been formed in advance on the surface ofthe reflection coating 14 a or the half-reflective coating 14 b or thereflecting member 15 a, 17 a or the half-reflecting member 15 b, 17 b.

The reflecting member 15 a, 17 a or the reflection coating 14 a on theresin member 16 may not be a reflective surface but can be a paintedsurface.

The state of reflection from the surface of a half-reflective coating 14b or the state of light transmission as seen from the rear surfacethereof may be given a variety by overlaying a total reflection coatingover a part of the half-reflective coating 14 b.

The invention claimed is:
 1. A process for surface treatment of a molded resin product, comprising: disposing an opaque coating film on a rear surface of a substrate made of a transparent resin, except for an area set aside for a patterned portion, filling the area set aside for the patterned portion with a transparent resin material after the opaque coating film is disposed on the rear surface of the substrate, the transparent resin material being formed flatly at the same height as the opaque coating film, and forming a half-reflective coating in a predetermined shape that covers at least a rear surface of the transparent resin material, so that a stereoscopic pattern or patterns is/are formed on an upper surface of the substrate and can be seen through the rear surface of the substrate.
 2. The process for surface treatment of a molded resin product according to claim 1, wherein the opaque coating film is laid over an entire rear surface of the substrate and removed from the area set aside for the patterned portion by irradiating the opaque coating film with a laser beam.
 3. The process for surface treatment of a molded resin product according to claim 1, wherein the opaque coating film is formed on the rear surface of the substrate by printing the opaque coating film in areas other than the area set aside for the patterned portion.
 4. The process for surface treatment of a molded resin product according to claim 1, wherein the transparent resin material is an ink, and the ink is embedded in the patterned portion as a transparent resin material.
 5. The process for surface treatment of a molded resin product according to claim 1, wherein an additive is incorporated into the transparent resin material.
 6. The process for surface treatment of a molded resin product according to claim 1, comprising: disposing a half-reflecting member having at least a half-reflective surface on the rear surface of the substrate so as to form the half-reflective coating on the patterned portion.
 7. The process for surface treatment of a molded resin product according to claim 6, wherein a total reflection coating is formed in a part of the half-reflective coating with which the patterned portion is provided.
 8. The process for surface treatment of a molded resin product according to claim 1, wherein the half-reflective coating is formed by hot stamping.
 9. The process for surface treatment of a molded resin product according to claim 1, wherein the transparent resin material in the patterned portion is devoid of any material of the opaque coating film in a thickness direction between the rear surface of the substrate and the half-reflective coating.
 10. A process for surface treatment of a molded resin product, comprising: disposing an opaque coating film on a rear surface of a substrate made of a transparent resin, except for an area set aside for a patterned portion, disposing a transparent resin material on the rear surface of the substrate in the area set aside for the patterned portion, the transparent resin material being formed flatly at the same height as the opaque coating film, and forming a half-reflective coating in a predetermined shape that covers at least a rear surface of the transparent resin material, so that a stereoscopic pattern or patterns is/are formed on an upper surface of the substrate and can be seen through the rear surface of the substrate, wherein the opaque coating film and transparent resin material do not overlap in a thickness direction.
 11. The process for surface treatment of a molded resin product according to claim 10, wherein the opaque coating film is laid over an entire rear surface of the substrate and removed from the area set aside for the patterned portion by irradiating the opaque coating film with a laser beam.
 12. The process for surface treatment of a molded resin product according to claim 10, wherein the opaque coating film is formed on the rear surface of the substrate by printing the opaque coating film in areas other than the area set aside for the patterned portion.
 13. The process for surface treatment of a molded resin product according to claim 10, wherein the transparent resin material is an ink, and the ink is embedded in the patterned portion as a transparent resin material.
 14. The process for surface treatment of a molded resin product according to claim 10, wherein an additive is incorporated into the transparent resin material.
 15. The process for surface treatment of a molded resin product according to claim 10, comprising: disposing a half-reflecting member having at least a half-reflective surface on the rear surface of the substrate so as to form the half-reflective coating on the patterned portion.
 16. The process for surface treatment of a molded resin product according to claim 15, wherein a total reflection coating is formed in a part of the half-reflective coating with which the patterned portion is provided.
 17. The process for surface treatment of a molded resin product according to claim 10, wherein the half-reflective coating is formed by hot stamping.
 18. The process for surface treatment of a molded resin product according to claim 10, wherein the transparent resin material in the patterned portion is devoid of any material of the opaque coating film in a thickness direction between the rear surface of the substrate and the half-reflective coating. 